I have a cloudant database with a lot of deleted docs. Since they can't be destroyed, I would like to make a filtered copy with the non deleted items to a temporary base, destroy the original one, and copy the temporary base to a fresh database with the same name as before.
The problem is when I destroy the base, the API keys generated are also destroyed...
So the front app calling the new base can't acces it !
I would like to manually create a user/password, so I can recreate the same user each time I destroy the database.
I don't know how to do it ?
Or is there another way to achieve my goal ??
To answer your actual question, you can't add "users" to a Cloudant account, only databases. You can, however, make API-keys that span multiple databases, which sounds like it could be what you want:
https://dx13.co.uk/articles/2016/04/11/using-a-cloudant-api-key-with-multiple-cloudant-databases-and-accounts/
But as was noted by bessbd above, if your data model relies on document deletion, you're working against the grain of Cloudant, and sooner or later you'll end up with problems.
And finally -- the doc links appear to work just fine.
Maybe some useful stuff here: https://blog.cloudant.com/2019/11/21/Best-and-Worst-Practices.html
[disclaimer, I wrote that]
Can you please expand a little further on your use case? Why do you want to get rid of the deleted docs? Is there a way to avoid deleting the docs? Also, have you already read https://cloud.ibm.com/docs/services/Cloudant?topic=cloudant-documents#tombstone-documents ?
Related
I have a split database and I have duplicated front-end file to make multiple copies for different users. Every-time a change is made on one front-end form, I want the other forms in other front-ends to always drop changes. How can I trap this write conflict to always drop changes maybe through VBA if possible?
Not quite sure what you mean by "drop changes" - the frontend should never be redesigned during normal use.
You must distribute a new copy of the frontend to the users.
A smooth and proven method using a shortcut and a script is described in my article:
Deploy and update a Microsoft Access application with one click
(If you don't have an account, browse for the link: Read the full article)
Edit:
If it is the data that is updated by several users, and you update via VBA, you may study another of my articles:
Handle concurrent update conflicts in Access silently
Though simple to use, the code is a bit too much to post here. It is also on GitHub:
VBA.ConcurrencyUpdates
I have just started using RavenDB on a personal project and so far inserting, updating and querying have all been very easy to implement. However, I have come across a situation where I need a GetOrCreate method and I'm wondering what the best way to achieve this is.
Specifically I am integrating with OpenID and once authentication has taken place the user is redirected to my site. At this point I'd either like to retrieve their user record from Raven (by querying on the ClaimsIdentifier property) or create a new record. The user's ID is currently being set by Raven.
Obviously I can write this in two statements but without some sort of transaction around the select and the create I could potentially end up with two user records in the database with the same claims identifier.
Is there anyway to achieve this kind of functionality? Possibly even more importantly is do you think I'm going down the wrong path. I'm assuming even if I could create a transaction it would make scaling out to multiple servers difficult and in anycase could add a performance bottle-neck.
Would a better approach be to have the Query and Create operations as separate statements and check for duplicates when the user is retrieved and merge at that point. Or do something similar but on a scheduled task?
I can't help but feel I'm missing something obvious here so any advice on this problem would be greatly appreciated.
Note: while scaling out to multiple servers may seem unnessecary for a personal project, I'm using it as an evaluation of Raven before using it in work.
Dan, although RavenDB has support for transactions, I wouldn't go that way in your case. Instead, you could just use the users ClaimsIdentifier as the user documents id, because they are granted to be unique.
Alternatively, you can also stay with user ids being generated by Raven (HiLo btw) and use the new UniqueConstraintsBundle, which lets you attribute certain properties to be unique. Internally it will create an additional document that has the value of your unique property as its id.
I'm working on an iOS app that creates "location sets" where each row contains a location name and a GeoPoint, and each set has its own name. Each of these sets are stored in an object inside our program (all belonging to the same class). Now we want to give users the capability to create sets and upload them to a database, allowing other users to access and download them to their device.
I've been looking in to back-end solutions for work like this, but pretty much everything I've found so far focuses on relational databases and adding and deleting rows and using SQL-like language to retrieve them. Is there a way to store these objects just as objects (and not unpack the info inside to tables), and then retrieve them? It feels like that would be a much simpler way of going about this.
I'm an absolute beginner when it comes to databases, so forgive me if there's info missing here that you would need to help me out. I'll make sure to keep checking back in case someone asks for more info.
Thanks!
Coredata might be useful for you as its based upon the entity. So you can play multiple things around it by using queries (predicates).
But if you just want to save and retrieve back, then as a simplest solution I would suggest to create array/dictionary with entity data, save that into NSUserDefaults so you can retrieve back same while re-launching the app.
Webservices for iOS development:
raywenderlich
icodeblog
WSDL Webservices
Response data parsing, it would be either JSON or XML:
JSON Parsing
XML Parsing
Hope these links would be helpful for you.
I ended up using Parse's mobile back-end service. That was the type of service I was looking for. I've found other similar services since then, like Applilcasa and StackMob, but we're pretty happy with Parse so far.
I have a small table in my Rails app that contains static data (user Roles). It shouldn't ever change. I'm wondering if it's possible to lock the table to keep anyone (namely developers) from accidentally changing it in production.
Or should I have not put that data into the database at all? Should it have been hardcoded somewhere to make editing more difficult and, at least, auditable (git blame)?
The right way to do this is with permissions. Change the ownership of the table to another user, and grant the production database user SELECT only.
I would say the right place for these kinds of things is probably the database. That way if they ever need to change, you can change them in the database, and you don't have to redeploy your application (assuming it will notice the change).
You didn't ask this, but your wording brought it to mind so I'll say it anyway: you should never need to explicitly LOCK a table with PostgreSQL. If you think this is something you need to do, you should make sure what you're worried about can actually happen under MVCC and that transactions aren't going to do the right thing for you.
I would probably make use of attr_accesible
if you write something like:
class Role < ActiveRecord::Base
attr_accessible #none
end
you could at least prevent any assignment from the rails side, but it does not prevent any direct modifications through developers with database access.
see also this thread: How I can set 'attr_accessible' in order to NOT allow access to ANY of the fields FOR a model using Ruby on Rails?
You can use a trigger to prevent updates to the table (assuming you can't add a new db user).
Or, use a view and ensure all read requests go through it. (probably by removing the ActiveRecord class that corresponds to the table.
I made a bad decision as I was designing a MongoDB database to embed a model rather than reference it in an associated model. Now I need to make the embedded model a referenced model, but there is already a healthy amount of data in the database (or document?).
I'm using Mongoid, so I reasoned I can just change embedded_in to referenced_in. Before I start, I figured I'd ask people who know better than I do. How can I transition the embedded data already in the database to the document for the associated model.
class Building
embeds_many :landlords
..
end
class Landlord
embedded_in :building
...
end
Short answer - Incrementally.
Create a copy of Landlord, name it Landlord2.
Make it referenced in Building.
Copy all data from Landlord to Landlord2.
Delete Landlord.
Rename Landlord2 to Landlord.
Users should not be able to CRUD Landlord during steps 3-5 (ideally). You still can get away with only locking CRUD on 4-5. Just make sure you make all updates that happened during copying, before removing Landlords.
Just chan ging the model like you have above will not work, the old data will still be in a different strucutre in the db.
Very similar the previous answer, one of the things I have done to do this migration before is to do it dynamically, while the system is running and being used by the users.
I had the data layer separated from the logic, so it let me add some preprocessors and inject code to do the following.
Lets say we start with the old datamodel, then release new code that does the following:
On every access to the document, you would have to check whether the embedded property exists, if it does, create a new entry associated as a reference and save to the database and delete the embedded property from the documents. Once this is done for a couple of days, a lot of my data got migrated and then I just had to run a similar script for everything that was not touched, made the job of migrating the data much easier and simpler and I did not have to run long running scripts or get the system offline to perform the conversion.
You may not ha ve that requirement, so Pick accordingly.